Methods and apparatus for constructing glass furnace structures

ABSTRACT

Methods and apparatus for constructing refractory structures, e.g., glass furnace regenerator structures and/or glass furnace structures having walls formed of refractory block and buck stays externally supporting the walls are provided. Opposed pairs of supports are connected to at least a respective one of the vertically oriented buck stays with cross-support beams spanning the refractory structure between a respective pair of the supports. An overhead crane assembly is supported by the cross-support beams. In such a manner, refractory components of the refractory structure (e.g., refractory wall blocks and/or refractory checker bricks) may be installed using the overhead crane assembly.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of commonly owned U.S. applicationSer. No. 14/859,820, filed Sep. 21, 2015 (now U.S. Pat. No. 10,227,220),which is based on and claims domestic priority benefits under 35 USC §119(e) from U.S. Provisional Application Ser. No. 62/111,275 filed onFeb. 3, 2015 and 62/053,403 filed on Sep. 22, 2014, and also claimsforeign priority benefits under 35 USC § 119(a) from GB 1503121.4 filedon Feb. 25, 2015, the entire content of each such prior filedapplication being expressly incorporated hereinto by reference.

FIELD

The embodiments disclosed herein relate generally to methods andapparatus for constructing refractory structures associated with glassfurnaces.

BACKGROUND

In the manufacturing process for making glass, raw materials includingsand, lime, soda ash and other ingredients are fed into a furnace,sometimes called a glass tank. The raw materials are subjected totemperature above about 2,800° F. in the glass furnace which causes theraw materials to melt and thereby form a molten bed of glass that exitsthe glass furnace for further downstream processing into glass products.

The most common way of heating the glass furnace is through thecombustion of a hydrocarbon fuel source, such as natural gas or oil. Thehydrocarbon fuel is mixed with combustion air inside the furnace andcombusted to thereby transfer the combustion heat energy to the rawmaterials and glass melt prior to exiting the furnace.

In order to improve the thermal efficiency of the combustion process,the combustion air used to combust the fuel is preheated by means ofregenerator structures. More specifically, a supply of combustion air ispreheated in a honeycombed pack of checker bricks contained within theinterior of the regenerator structure. Fresh combustion air is drawn upthrough the pack of heated checker bricks in the regenerator structureand preheated by means of heat transfer. The pre-heated combustion airmay then be mixed with the fuel, combusted. Waste combustion gas exitsthe glass furnace and passes through a second regenerator structure. Asthe waste gasses pass through the second regenerator the checkers in thepack are heated by means of heat transferred from the waste gas. After apredetermined time has elapsed (e.g., after about 15-30 minutes), theprocess cycle is reversed so that the checker bricks in one of theregenerator structures that were being heated by heat transfer with thewaste gas are then used to preheat the fresh combustion air while thechecker bricks in the other regenerator structures that were used topreheat the combustion air are then re-heated by heat transfer with thewaste combustion gas. See in this regard, U.S. Pat. No. 3,326,541 (theentire content of which is expressly incorporated hereinto byreference).

The current process for building glass furnace refractory structures,e.g., regenerators, glass furnaces, fore hearths and the like, is verylabor intensive taking many weeks as it requires the placement ofhundreds of thousands of refractory bricks that may be individuallycoated with mortar and positioned or in some cases essentially dry setwith minimal (if any) mortar. As is well known in the glass makingindustry, the joints associated with the bricks of the furnacerefractory structures are the weakest part of the structure and areconsequently more readily susceptible to degradation by the corrosivehot gasses passing therethrough. As the brick joints begin to erode, thewalls forming the refractory structure face increased attack as thecorrosive gasses begin to condense and dissolve the refractory materialsforming the bricks thereby weakening the structure. As the structurebecomes weakened, the glass furnace itself may become compromised andfail which could then require a complete shut down and rebuildingoperation.

It can be appreciated therefore, that if the refractory structures couldbe fabricated from larger refractory blocks, then fewer joints wouldensue thereby prolonging the regenerator structure's useful life andminimizing down time due to rebuilding. However, while large refractoryblocks can be fabricated by pressing, molding or casting a refractorymaterial, it is problematic to install such blocks during constructionof a large-scale refractory structure.

In addition to the problems noted above, many of the components of therefractory structure, e.g., checker bricks used in glass regeneratorstructures, need to be replaced near or at the end of their useful lifein order to maintain optimal production efficiencies. It is currentlydifficult to replace such components, e.g., the checker bricks, when itmay be desired for them to do so.

What has been needed therefore are improvements in apparatus and methodswhereby refractory structures may be efficiently and economicallyconstructed and/or re-built. It is towards providing such improvementsthat the embodiments of the present invention are directed.

SUMMARY

In general, the embodiments disclosed herein are directed toward methodsand apparatus for constructing a refractory structures, e.g., glassfurnace regenerators, glass furnace systems such as glass furnacerefiners, and the like having walls formed of refractory block and buckstays externally supporting the walls. According to one embodiment, theapparatus includes opposed pairs of supports connected to at least arespective one of the vertically oriented buck stays, cross-supportbeams spanning the refractory structure between a respective pair of thesupports, and an overhead crane assembly supported by the cross-supportbeams.

The pairs of supports may comprise a plurality of foundation beamsrigidly installed between respective adjacent pairs of buck stays andpairs of upright support beams each supported by a respective one of thefoundation beams. According to other embodiments, the pairs of supportsmay comprise an arch support extending between and connected to anadjacent pair of the buck stays, wherein the cross-support beams areattached to an apex of the arch support. Alternatively or additionally,the pairs of supports may comprise a pair of upwardly convergentsupports extending between and connected to an adjacent pair of the buckstays, wherein the cross-support beams are attached to an apex of theconvergent supports.

In some embodiments the apparatus further comprises buck stay extensionmembers rigidly connected to an upper terminal end of predetermined buckstays, and cross-support beams spanning the refractory structure betweenrespective pairs of the buck stay extension members.

In some embodiments the hoist assembly comprises a monorail attached topredetermined ones of the buck stays. The monorail may be rigidlyconnected to an inboard surface of the predetermined ones of the buckstays.

In some embodiments the apparatus further comprises a hanger memberhaving one leg attached rigidly to the predetermined ones of the buckstays, and another leg rigidly attached to the monorail. The hangermember may be generally U-shaped.

The overhead crane assembly may comprise a raceway beam longitudinallyextending relative to the refractory structure and dependently supportedby the cross-support beams, and a hoist assembly moveably mounted to theraceway beam. According to certain embodiments, the overhead craneassembly may comprise a pair of the raceway beams, and a bridge beammoveable mounted to the pair of raceway beams for reciprocal movementstherealong in a longitudinal direction of the refractory structure. Thehoist assembly may thus be moveably mounted to the bridge beam forreciprocal movements therealong in a latitudinal direction of therefractory structure.

One end portion of the raceway beams may be supported in a cantilevermanner according to some embodiments by a respective pair of supportbeams and cross-support beam and so as to extend beyond a respective endof the regenerator structure.

The regenerator structure may further include a port and an operatorplatform below the port. In such embodiments, the foundation beams maybe rigidly positioned between the respective pairs of buck stays at orabove the operator platform.

According to other embodiments, a method for constructing a regeneratorstructure is provided by (i) connecting opposed pairs of supports to arespective one of vertically oriented buck stays, (ii) latitudinallyspanning the refractory structure with cross-support beams connectedbetween respective pairs of the upright supports, and (iii) supportingan overhead crane assembly by the cross-support beams.

Step (i) may include (ia) rigidly installing a plurality of foundationbeams between respective adjacent pairs of buck stays, and (ib)supporting pairs of upright support beams by a respective one of thefoundation beams. Alternatively or additionally, step (i) may compriseextending and connecting arch supports between adjacent pairs of thebuck stays, and attaching the cross-support beams to an apex of arespective one of the arch supports. Other embodiments may includeextending and connecting pairs of upwardly convergent supports betweenan adjacent pair of the buck stays, and attaching the cross-supportbeams to an apex of a respective one of the convergent supports.

In some embodiments of the method the refractory structure is a glassfurnace regenerator structure having walls comprised of refractoryblocks and an interior comprised of checker bricks, and wherein themethod further comprises operating the overhead crane assembly so as toposition the refractory blocks and/or the checker bricks.

According to embodiments, the overhead crane assembly will be providedby (a) installing a pair of raceway beams which longitudinally extendrelative to the refractory structure and are dependently supported bythe cross-support beams; (b) moveably mounting a bridge beam to the pairof raceway beams for reciprocal movements therealong in a longitudinaldirection of the refractory structure; and (c) moveably mounting a hoistto the bridge beam for reciprocal movements therealong in a latitudinaldirection of the refractory structure.

The raceway beams may be installed in such a manner that one end portionof the raceway beams is supported in a cantilever manner by a respectivepair of support beams and a cross-support beam to thereby cause the oneend of the raceway beams to extend beyond a respective end of therefractory structure. Additionally or alternatively, the foundationbeams are installed at a position between the respective pairs of buckstays which is at or above an operator platform.

In some embodiments the refractory structure further includes a port andan operator platform below the port, and step (a) comprises rigidlyinstalling the foundation beams at a position between the respectivepairs of buck stays which is at or above the operator platform

These and other aspects and advantages of the present invention willbecome more clear after careful consideration is given to the followingdetailed description of the preferred exemplary embodiments thereof.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

The disclosed embodiments of the present invention will be better andmore completely understood by referring to the following detaileddescription of exemplary non-limiting illustrative embodiments inconjunction with the drawings of which:

FIG. 1 is a perspective view of a regenerator structure showing anapparatus in accordance with an embodiment of the present invention;

FIG. 2 is a partial end elevation view of the regenerator structure asdepicted in FIG. 1;

FIG. 3A is a perspective view of a regenerator structure prior toinstallation of apparatus in accordance with an embodiment of thepresent invention;

FIG. 3B is an enlarged perspective view of an end of the regeneratorstructure depicted in FIG. 3A;

FIG. 3C is an enlarged perspective view similar to FIG. 3A but showingan installation sequence for the overhead crane apparatus;

FIG. 3D is an enlarged perspective view similar to FIG. 3C but showingthe overhead crane apparatus completely installed;

FIG. 4 is a perspective view of a cross-fired glass furnace systemshowing the apparatus in accordance with other embodiments of thepresent invention;

FIGS. 5 and 6 are a side and end elevational views, respectively, of theupper portion of the glass furnace system depicted in FIG. 4;

FIG. 7 is a perspective view of the glass furnace section of the systemdepicted in FIG. 4;

FIG. 8 is an end elevational view of the glass furnace section depictedin FIG. 7;

FIGS. 9-13 are respective schematic perspective views of alternativesupport arrangements according to other embodiments of the invention.

DETAILED DESCRIPTION

Accompanying FIG. 1 schematically depicts a perspective view of aregenerator structure 10 showing an overhead crane apparatus 50 inaccordance with an embodiment of the present invention. As shown, theregenerator structure 10 is constructed of large pre-cast refractorblocks (a few of which are identified by reference numeral 12) stackedon a foundation 14 to thereby form side and end walls 16, 18,respectively. It will be appreciated that the regenerator structure 10is used in operative combination with a glass furnace (not shown). Theregenerator structure 10 generally depicted in the accompanying FIGURESis of a type used for side-fired glass furnaces. However, the attributesof the embodiments of the invention to be described herein are equallyapplicable to other glass furnace designs, e.g. end-fired glassfurnaces.

The regenerator structure 10 includes a series of ports 10-1 which areused to introduce pre-heated combustion air into the glass furnace (notshown) or to exhaust combustion gas from the furnace depending on theoperational cycle. The top of the regenerator structure 10 is cappedwith crowns (a representative few of which are noted by referencenumeral 10-2). An operator platform 10-3 typically is provided near theports 10-1. The walls 16, 18 are structurally supported by externalupright structural beams known colloquially as buck stays 20. As isshown in FIGS. 3A and 3B, the buck stays 20 are compressively heldagainst the walls by means of tie rods 22 extending between opposedpairs of buck stays 20 both latitudinally and longitudinally relative tothe regenerator structure 10.

FIG. 1 depicts a state whereby the walls 16, 18 have been constructed ofrelatively large monolithic refractory blocks 12 and the checker bricks(a supply of which stacked on the platform 10-3 is denoted in FIG. 1 byreference numeral 24) are being stacked within the interior space of theregenerator structure 10. The apparatus 50 in the state shown in FIG. 1has thus been employed to install the refractory blocks 12 when formingthe walls 16, 18 and is thereby in the process of installing the checkerbricks 24 within the interior defined by such walls 16, 18. For thisreason, a few of the crowns 10-2 have not yet been installed at one endof the regenerator structure 10 so as to permit access into its interiorspace.

The overhead crane apparatus 50 in accordance with an embodiment of theinvention is depicted as including laterally spaced-apart upright pairsof upright support beams 52 and a cross-support beam 54 spanning thedistance therebetween. A foundation beam 55 extends between and isrigidly attached (e.g., by welding) to an adjacent pair of buck stays 20so as to structurally support the upright and cross-support beams 52,54. Each of the foundation beams 55 is most preferably connected betweenthe adjacent pair of buck stays 20 at or just above the platform 10-3.

The cross-support beams 52, 54 dependently support a pair of runwaybeams 56 between which is connected a travelling bridge beam 58. Thebridge beam 58 includes an overhead travelling hoist 60. As is shown inFIG. 2, the runway beams 56 are supported in a cantilever manner by theend-most upright and cross-support beams 52, 54 to that the terminal endportions extend beyond the wall 18 of the regenerator structure 10thereby enabling access to the stacked supply of checker bricks 24 onthe platform 10-3.

Suitable operator controlled motors (not shown) are provided with thebridge beam 58 to allow it to reciprocally travel along the runway beams56 in a longitudinal direction of the regenerator structure (i.e., inthe direction of arrow A1 in FIG. 1). Similarly, operator controlledmotors (not shown) are provided with the hoist 60 to allow it to travelreciprocally along the bridge beam in a latitudinal direction of theregenerator structure 10 (i.e., in a direction of arrow A2 in FIG. 1).The hoist 60 is connected to a suitable lifting sling 62 to allow thestacked supply of checker bricks 24 to be lifted up and into theinterior of the regenerator structure 10, e.g., by suitably operatingthe bridge beam 58 and hoist 60 so as to travel in the directions ofarrows A1 and A2 while simultaneously causing the hoist 62 to raise orlower the checker bricks 24 (i.e., in a direction transverse to arrowsA1 and A2). In such a manner, therefore, the checker bricks within theregenerator structure 10 may be replaced. It will be appreciated thatthe operation as described above will also allow the refractory blocks12 to be installed as may be needed.

FIGS. 3A-3D show a sequence by which the overhead crane apparatus 50 maybe assembled relative to an existing regenerator structure 10. As waspreviously noted, the buck stays 20 are compressively held against therefractory blocks 12 forming the walls 16, 18 of the regeneratorstructure by means of tie rods 22. FIGS. 3A and 3B therefore show anexisting regenerator structure 10 with the tie rods 22 in place. As isshown in FIG. 3C, the tie rods 22 have been removed and a foundationbeam 55, upright support beam 54 and cross-support beam 56 installed asdescribed previously. The particular sequence of removing the tie rods22 and installation of the foundation beam 55, upright support beam 52and cross-support beam 54 is not critical provided that there is nostructural interference therebetween. Thus, the tie rods 22 can beremoved before or after installation of the foundation beam 55, uprightsupport beam 52 and cross-support beam 54 although it is typicallypreferred that the tie rods 22 be removed first as this ensures thatthey will not structurally interfere with any of the later installedbeams.

FIG. 3D shows the runway beams 56 having been installed by connection tothe cross-support beams 54. Although not shown in FIG. 3D, the bridgebeam 58 with the hoist 60 operatively connected thereto may likewise beinstalled onto the runway beams 56. Thereafter, the installation of therefractory blocks 12 and/or checker bricks 24 may proceed in the manneras previously described.

A cross-fired glass furnace system 70 is depicted in FIGS. 4-6 as beingcomprised of a central glass furnace structure 75 (e.g., a floatfurnace) and opposed pairs of regenerator structures 10, 10′ operativelyinteracting with the furnace structure 75. Each of the regeneratorstructures 10, 10′ are as described previously with reference to FIGS.1-3D but are substantial mirror images of one another. Thus,corresponding structure described above with reference to regenerator 10is shown by the same reference numeral in regenerator 10′, but with aprime (′) identifier. Thus, separate explanations of such correspondingstructures for the regenerators 10, 10′ will not be repeated.

The glass furnace structure 75, like the regenerators 10, 10′, includesvertically oriented buck stays 80. The overhead crane apparatus employedfor the glass furnace structure 75 is depicted as including laterallyspaced-apart upright pairs of upright support beams 82 and across-support beam 84 spanning the distance therebetween. A foundationbeam 85 extends between and is rigidly attached (e.g., by welding) to anadjacent pair of buck stays 80 so as to structurally support the uprightand cross-support beams 82, 84.

The cross-support beams 82, 84 dependently support a pair of runwaybeams 86 between which is connected a travelling bridge beam 88. Thebridge beam 88 includes an overhead travelling hoist 90. The runwaybeams 86 are preferably supported in a cantilever manner by the end-mostupright and cross-support beams 82, 84 so that the terminal end portionsextend beyond the end wall of the furnace structure 75 thereby enablingaccess to structural components to be hoisted by the travelling hoist90.

Suitable operator controlled motors (not shown) are provided with thebridge beam 88 to allow it to reciprocally travel along the runway beams86 in a longitudinal direction of the regenerator structure (i.e., inthe direction of arrow A1 in FIG. 4). Similarly, operator controlledmotors (not shown) are provided with the hoist 90 to allow it to travelreciprocally along the bridge beam in a latitudinal direction of thefurnace structure 75 (i.e., in a direction of arrow A2 in FIG. 4).

FIGS. 9 and 10 depict alternative embodiments for supporting thecross-supports beams 52, 52′ of the regenerator structures 10, 10′,respectively, and/or the cross-support beams 82 of the glass furnacestructure 75. In this regard, FIGS. 9 and 10 are depicted inrelationship to supporting the cross-support beams 52 the regeneratorstructure 10, but the disclosed embodiments are equally applicable tothe regenerator structure 10′ and the glass furnace structure 75.

As shown in FIG. 9, the cross-support beam 52 may be attached to anarched support member 100 which extends between and is rigidly connectedto (e.g., via welding) an adjacent pair of buck stays 20. Thecross-support beam 52 may be connected directly to an apex region of thearched support member 100. Alternatively, as depicted in FIG. 9, apedestal support 102 may be provided extending upwardly from the apexregion of the arched support member 100 to which an end of thecross-support beam 52 is attached.

In a similar manner, FIG. 10 shows another embodiment whereby a pair ofupwardly convergent support members 110, 112 extend between and arerigidly connected to an adjacent pair of buck stays 20. The terminalends of the convergent support members 110, 112 may be connecteddirectly to one another and to an end of the cross-support beam 52(e.g., by welding). Alternatively, as depicted the terminal ends of theconvergent support members 110, 112 may be rigidly connected to anupwardly extending pedestal support 114 which in turn is connected tothe cross-support support beam 52.

Another embodiment is depicted in FIG. 11 whereby a buck stay extensionmember 20-1 is rigidly fixed to (e.g., via welding) an upper terminalend of the buck stays. The cross-support beam 54 may therefore berigidly fixed to opposing pairs of such extension members 20-1 so as tospan the distance across the regenerator structure. The runway beams 56may therefore be connected directly to the cross-support beams 54.According to the embodiment depicted in FIG. 11, therefore, the use ofupright support beams 52 and foundation beams 55 is not necessarilyrequired.

Accompanying FIGS. 12 and 13 depict embodiments of the invention whichemploy a monorail system. In this regard, as shown in FIG. 12, amonorail member 200 is attached to selected ones of the buck stays 20 bygenerally inverted U-shaped hangers 202. As shown, the hangers 202include an outboard vertical leg 202 a and an inboard vertical leg 202 bconnected to one another by a horizontal leg 202 c. The monorail 200 isconnected rigidly to the inboard leg 202 b and supports a travellinghoist 60 of the variety discussed previously. The relative lengths ofthe legs 202 a and 202 b can be predetermined so as to accommodatevarying height requirements that may be needed from one regeneratorstructure to another.

FIG. 13 is similar to the embodiment depicted in FIG. 12 except that themonorail 200 is connected rigidly to an inboard face of the buck stays20.

Although the embodiments have been described in relation to across-fired glass furnace system, the principles of the invention maylikewise be embodied in any glass furnace design, such as floatfurnaces, end-fired furnaces, unit melters with recuperators andelectric furnaces with shelf, sidewall or bottom electrodes.

It will therefore be understood that the description provided herein ispresently considered to be the most practical and preferred embodimentsof the invention. Thus, the invention is not to be limited to thedisclosed embodiments, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope thereof.

What is claimed is:
 1. A combination comprising: a refractory structurehaving an opposed pair of side walls and upright buckstays supportingthe side walls; and a construction apparatus for positionally assemblingstructural components of the refractory structure, wherein theconstruction apparatus comprises: (i) an opposed plurality of foundationbeams rigidly installed between respective longitudinally separatedpairs of the buckstays adjacent the exterior surfaces of the opposedpair of side walls; (ii) opposed pairs of upright support beamspositioned so that a lower end of a respective pair of upright supportbeams is rigidly connected to and supported by respective ones of thefoundation beams and an upper end of the upright support beams extendsupwardly above the opposed pair of side walls; (iii) cross-support beamslatitudinally connecting respective upper ends of the opposed pairs ofupright support beams such that the cross-support beams latitudinallyspan the interior space of the refractory structure; (iv) a pair ofraceway beams which longitudinally extend relative to the refractorystructure connected to the cross-support beams so that the raceway beamsare dependently supported by the cross-support beams; and (v) a hoistassembly operably connected to the pair of raceway beams to allow thestructural components of the refractory structure to be positionallyassembled.
 2. The combination of claim 1, wherein an end portion of theraceway beams extends in a cantilever manner beyond one of the end wallsof the refractory structure.
 3. The combination of claim 1, wherein thestructural components are refractory blocks for assembly with the sidewalls of the refractory structure and/or checker bricks for assembly inan interior space of the refractory structure, and wherein the hoistassembly comprises: a bridge beam moveably mounted to the pair ofraceway beams for reciprocal movements therealong in a longitudinaldirection of the refractory structure; and a hoist moveably mounted tothe bridge beam for reciprocal movements therealong in a latitudinaldirection of the refractory structure.
 4. The combination according toclaim 1, wherein the foundation beams comprise an arch support extendingbetween and connected to the respective longitudinally separated pairsof buckstay supports, wherein the upright support beams are attached toan apex of the arch support.
 5. The combination according to claim 1,wherein the foundation beams comprise a pair of upwardly convergentsupports extending between and connected to the respectivelongitudinally separated pairs of buckstays, wherein the upright supportbeams are attached to an apex of the convergent supports.
 6. Thecombination according to claim 1, wherein the refractory structurefurther includes a port and an operator platform below the port, andwherein the foundation beams are rigidly positioned between therespective pairs of buck stays at or above the operator platform.
 7. Thecombination according to claim 1, wherein the foundation beams aresubstantially horizontally installed between the respectivelongitudinally separated pairs of buckstays.
 8. A method of forming thecombination of claim 1 to allow positional assembly of refractorycomponents to construct the refractory structure, wherein the methodcomprises the steps of: (a) rigidly connecting the opposed plurality offoundation beams between the respective longitudinally separated pairsof the buckstays adjacent the exterior surfaces of the opposed pair ofside walls; (b) positioning the opposed pairs of upright support beamsso that the lower end of the respective pair of upright support beams isrigidly connected to and supported by respective ones of the foundationbeams and the upper end of the upright support beams extends upwardlybeyond the side walls; (c) latitudinally spanning the refractorystructure with the cross-support beams by connecting the cross-supportbeams between respective pairs of the upright support beams; (d)supporting the pair of raceway beams by the cross-support beams; and (e)operably installing the hoist assembly on the pair of raceway beams toallow the refractory components of the refractory structure to bepositionally assembled.
 9. The method according to claim 8, wherein step(d) comprises supporting the pair of raceway beams by the cross-supportbeams such that one end portion of the raceway beams is supported in acantilever manner by a respective pair of the upright support beams anda cross support beam to thereby cause the one end of the raceway beamsto extend beyond a respective end wall of the refractory structure. 10.The method according to claim 8, wherein step (a) comprises extendingand connecting arch supports between adjacent pairs of the buck stays,and attaching the cross-support beams to an apex of a respective one ofthe arch supports.
 11. The method according to claim 8, wherein step (a)comprises extending and connecting pairs of upwardly convergent supportsbetween an adjacent pair of the buck stays, and attaching thecross-support beams to an apex of a respective one of the convergentsupports.
 12. The method according to claim 8, wherein the methodfurther comprises operating the hoist assembly so as to positionrefractory blocks and/or checker bricks for assembly.
 13. The methodaccording to claim 8, wherein the refractory structure further includesa port and an operator platform below the port, and wherein step (a)comprises rigidly installing the foundation beams at a position betweenthe respective pairs of buckstays which is at or above the operatorplatform.
 14. The method according to claim 8, further comprisingremoving tie rods interconnecting the buck stays.
 15. The methodaccording to claim 8, wherein step (e) comprises: (e1) moveably mountinga bridge beam to the pair of raceway beams for reciprocal movementstherealong in a longitudinal direction of the refractory structure; and(e2) moveably mounting a hoist to the bridge beam for reciprocalmovements therealong in a latitudinal direction of the refractorystructure.